1. Field of the Invention
This invention relates generally to an inflatable apparatus for use as a float in water or as a cushion on a firm surface, and more particularly concerns an inflatable air mattress having a mat portion that is bendable in an inflated condition particularly along transverse and oblique lines between portions of reduced thickness, allowing the mat portion to be rolled up or folded in an inflated condition and allowing the mat portion to cradle a person reclining on the inflatable mattress in water.
2. Description of Related Art
Inflatable air mattresses, cushions, and the like of the type having a typically rectangular main body portion with longitudinal or tubular air chambers are well known in the art. One drawback of such inflatable devices is that in a fully inflatable condition they can be generally unwieldy to carry, and are usually quite rigid. When such an inflatable air mattress is used as a flotation mattress in water, a person resting on the flotation mattress can typically also slide or roll off of the flotation mattress when the person's weight is not well centered on the flotation mattress, making it sometimes difficult for the person to board the flotation mattress when it is in water.
It would therefore be desirable to provide such an inflatable flotation mattress that is foldable or bendable in at least one direction to allow the mattress to be folded or rolled in a fully inflated condition, for easy carrying, transportation or storage. It would also be desirable to provide such an inflatable flotation mattress that is foldable or bendable in more than one direction to allow the mattress to cradle the body of a person resting on the mattress by becoming indented or depressed by the weight of the person in a configuration that conforms to the body weight of the person.
One conventional inflatable flotation mattress providing bend or fold lines allows the mattress to be rolled about a pillow portion in a fully inflated condition. That flotation mattress design includes a rectangular inflatable mat portion with side-by-side dual sets of symmetrically arranged diamond shaped air chambers, formed by alternating transverse sinusoidal heat seal lines shifted by half of the repeating sine wave pattern. The transverse heat seal lines allow the mat portion to be rolled. The heat seal lines also form a pattern of intersecting folding lines allowing the mat portion to conform to the body of a person floating on the mat in water. It has been found, however, that full inflation of the air chambers tends to pull opposite sides of the mat portion together, causing distorting wrinkles in the air chambers. It is also known that oblique orientation of air chambers can cause the mat portion to be slanted to one side or the other when fully inflated.
It is therefore desirable to provide for an inflatable mattress that can be used as a flotation mattress, that is foldable, bendable, or rollable in multiple directions to allow the mattress to be rolled or folded when fully inflated, and to sufficiently cradle the parts of the body of a person resting on the mattress, and to support the person without distorting the shape of the mat portion of the mattress, and without causing the mat portion to be slanted to one side, when fully inflated. The present invention meets these needs.